/**
* Copyright 2012 Netflix, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.netflix.hystrix.strategy.eventnotifier;
import java.util.List;
import com.netflix.hystrix.HystrixCommandKey;
import com.netflix.hystrix.HystrixCommandProperties.ExecutionIsolationStrategy;
import com.netflix.hystrix.HystrixEventType;
import com.netflix.hystrix.strategy.HystrixPlugins;
/**
* Abstract EventNotifier that allows receiving notifications for different events with default implementations.
* <p>
* See {@link HystrixPlugins} or the Hystrix GitHub Wiki for information on configuring plugins: <a
* href="https://github.com/Netflix/Hystrix/wiki/Plugins">https://github.com/Netflix/Hystrix/wiki/Plugins</a>.
* <p>
* <b>Note on thread-safety and performance</b>
* <p>
* A single implementation of this class will be used globally so methods on this class will be invoked concurrently from multiple threads so all functionality must be thread-safe.
* <p>
* Methods are also invoked synchronously and will add to execution time of the commands so all behavior should be fast. If anything time-consuming is to be done it should be spawned asynchronously
* onto separate worker threads.
*/
public abstract class HystrixEventNotifier {
/**
* Called for every event fired.
* <p>
* <b>Default Implementation: </b> Does nothing
*
* @param eventType event type
* @param key event key
*/
public void markEvent(HystrixEventType eventType, HystrixCommandKey key) {
// do nothing
}
/**
* Called after a command is executed using thread isolation.
* <p>
* Will not get called if a command is rejected, short-circuited etc.
* <p>
* <b>Default Implementation: </b> Does nothing
*
* @param key
* {@link HystrixCommandKey} of command instance.
* @param isolationStrategy
* {@link ExecutionIsolationStrategy} the isolation strategy used by the command when executed
* @param duration
* time in milliseconds of executing <code>run()</code> method
* @param eventsDuringExecution
* {@code List<HystrixEventType>} of events occurred during execution.
*/
public void markCommandExecution(HystrixCommandKey key, ExecutionIsolationStrategy isolationStrategy, int duration, List<HystrixEventType> eventsDuringExecution) {
// do nothing
}
}